[Association of ambient fine particulate air pollution with hospitalization costs and stays for depression in China: a multicity analysis].

Objective: To explore the effect of fine particulate matter (PM2.5) pollution on depression hospitalization cost and length of stay in 57 cities of China. Methods: A total of 84 207 patients with depression in 57 cities of China from January 2013 to December 2017 were selected as the subjects. The demographic characteristics and hospitalization status of the patients were obtained from the database of basic medical insurance for urban workers and urban residents in China. The environmental exposure data of the same period were obtained from the national air quality real-time release platform of China Environmental Monitoring Station. A generalized additive model based on quasi-Poisson distribution was used to analyze PM2.5 exposure effect in each city, and the nonlinear mixing of moving average temperature, relative humidity and date was controlled by natural smooth spline function. Results: Among the included cities, southern cities accounted for 50.88% (29), and the number of female inpatients, hospitalization costs and hospitalization days accounted for 62.65%, 63.50% and 60.85% (42 735 cases, 567.78 million yuan and 1.14 million days, respectively). The proportion of hospitalized cases, hospitalization cost and length of stay in the age group of 40 to 64 years old were 59.15% (40 346 cases), 53.92% (482.15 million yuan) and 52.07% (0.98 million days), respectively. PM2.5 level was positively correlated with the number of hospitalized cases with depression, hospitalization cost and length of stay. When the 3-day moving average of PM2.5 exposure level increased by 10 μg/m3, the number of hospitalization cases increased by 0.64%. The attributed percentage (95%CI) of hospitalized cases, hospitalization costs and length of stay were 3.35% (0.57%-6.04%), 3.04% (0.52%-5.48%) and 3.07% (0.49%-5.56%), respectively. Subgroup analysis showed that the attributed percentage of hospitalization cases, hospitalization cost and length of stay to PM2.5 exposure ranged from 3.97% to 4.68%, 4.04% to 4.33% and 4.13% to 4.30% in northern China, male and cold season, respectively. Conclusion: PM2.5 exposure is associated with the increase of hospitalization cost and length of stay among Chinese urban population with depression.目的： 探讨大气细颗粒物（PM2.5）污染对中国57个城市抑郁症患者住院费用和时间的影响。 方法： 以2013年1月至2017年12月中国57个城市的84 207例抑郁症患者为研究对象。从中国城镇职工基本医疗保险和城镇居民基本医疗保险数据库获取患者的人口学特征和住院情况，同期环境暴露数据源自中国环境监测总站全国城市空气质量实时发布平台的全国空气质量数据。利用基于类泊松分布的广义相加模型分析各城市PM2.5暴露效应，采用自然平滑样条函数控制移动平均气温、相对湿度和日期的非线性混杂。 结果： 所纳入城市中，南方城市占50.88%（29个）；女性住院病例数、住院费用和住院天数分别占62.65%、63.50%和60.85%（分别为42 735例、56 778.19万元和114.16万天）。40~64岁年龄组住院病例数、住院费用和住院天数占比分别为59.15%（40 346例）、53.92%（48 214.60万元）和52.07%（97.68万天）。大气PM2.5水平与抑郁症住院病例数、住院费用和住院天数呈正向关联，滞后0~2 d PM2.5暴露水平的移动平均值每增加10 μg/m3，抑郁症住院人数相应增加0.64%；住院病例数、住院费用与住院天数的归因于PM2.5暴露的百分比（95%CI）分别为3.35%（0.57%，6.04%）、3.04%（0.52%，5.48%）和3.07%（0.49%，5.56%）。亚组分析结果显示，北方、男性和寒冷季节抑郁症住院比例、住院费用和住院天数归因于PM2.5暴露的百分比分别为3.97%~4.68%、4.04%~4.33%和4.13%~4.30%。 结论： 大气PM2.5暴露可增加中国城市人群抑郁症病例住院费用和时间。.